The present invention relates to methods for imaging fluid flow in a sample and, more particularly, to novel methods using magnetic field gradient and radio-frequency pulse signal sequences which permit nuclear magnetic resonance (NMR) angiographic images to be noninvasively obtained of any medically significant anatomy portion in which fluid flow occurs.
It is well known to provide images of angiographic data, indicating the flow of bodily fluids through various bodily passages, for medical diagnostic purposes. Typically, angiographic procedures have utilized ionizing radiation and have frequently required the use of contrast agents. It is well known that the use of contrast media occasions patient discomfort and is not without a certain probability of physical risk. It is not only desirable to provide angiographic images utilizing nuclear magnetic resonance processes to eliminate the use of ionizing radiation, but it is also desirable to provide NMR angiographic images which visualize all of the major fluid-carrying vessels of the anatomical portion being imaged, with a high degree of suppression of non-moving nuclear spins and without the use of any contrast agent.